COMPRESSED FOAM PADS

Abstract: Method and apparatus for forming and packaging pad-like articles (10) of resilient compressible foam having one dimension (thickness) smaller than its other two dimensions. The pad-like articles are successively fed into an entry to a compression mechanism (20) having an interior space (21) in which each article is turned on itself to compress it in the one dimension (thickness-upon-thickness) by movement of bounding surfaces (22) of the interior space. The compressed pad-like articles (10c) are then pushed from the compression mechanism transversely to said movement of bounding surfaces of the interior space and a containing wrapping applied.

Description: TITLE: COMPRESSED FOAM PADS DESCRIPTION ■ This invention relates to forming and packaging articles of compressible material, typically resilient foam or sponge material (hereinafter called "foam"). We are particularly interested in providing foam pad¬ like articles that are compressed, preferably at least partially rolled up within a wrapper, and further preferably have useful impregnation, for example with soap or detergent or sanitary agent (but generally any useful material), in a quantity up to the maximum capable of being held by the article as a pad partially compressed within its wrapper. It is an object of this invention to provide practical and novel method and apparatus for such purpose. According to one aspect of this invention, there is provided a method of forming and packaging pad-like articles of resilient compressible foam having one dimension (thickness) smaller than its other two dimensions, the method comprising the successive steps, for successive articles, of: (a) feeding the pad-like articles successively into an entry to a compression mechanism having an interior space nominally corresponding to exterior compressed form of the pads as desired for the articles and an entry to the interior space that is preferably not wider than the one dimension (thickness) of the pads prior to compression (b) turning each pad on itself in the interior space of the compression mechanism to compress it in the one dimension (thickness-upon-thickness) by movement of bounding surfaces of the interior space (c) pushing the compressed pads from the compression mechanism transversely to said movement of bounding surfaces of the interior space (d) forming a package as a said article by applying a containing wrapping about the rolled up pads outside the compression mechanism. Preferably, the articles are effectively spun in the interior space of the compression mechanism at completion of their turning on themselves in the one dimension so as to be at least partially rolled up as translated therefrom, further preferably into a guide about which continuous wrapping sheet is fed and formed to enclose the rolled up articles. Sealing of the wrapping material to itself is preferred both lengthwise of the rolled-up articles and between them. According to another aspect of this invention, there is provided apparatus for forming and packaging articles of resilient compressible foam, comprising first means for feeding pad-like foam bodies each having one dimension (thickness) less than its other two dimensions with a leading edge in said one dimension; second means for accepting said pad-like foam bodies by their leading edges first into an interior space within which said pad-like foam bodies are turned on themselves in the one dimension for at least partial rolling up (thickness-upon-thickness) , by movement of one or more parts bounding that interior space; third means for translating such rolled-up bodies from the second means transversely of movement of the bounding part or parts; and fourth means for accepting such rolled-up bodies from the second means and applying a constraining wrapping thereabout. It is feasible for the first means to serve both to feed the pad-like foam bodies and begin compression of them. Accordingly exit from the first means can be of lesser spacing than the thickness of the pad-like bodies. One suitable provision comprises rollers at said lesser spacing, conveniently a pair of driven rollers opposite another driven roller, say with the pair of rollers above the other roller. It is preferred that some or all such rollers are of surface-gripping type relative to the pad¬ like foam bodies. It is preferred that the second means have a cylindrical locus for axes of rollers constituting its moving parts bounding its interior space within which compression takes place; and further that at least some of those bounding rollers are driven, even where the first means positively feeds the pad-like articles through a spacing between the rollers first above mentioned (and whether such provision is seen as exit from the first means or as entry to the second means) . The interior space (then within the bounding rollers and thus generally cylindrical) will be of less volume than pad-like bodies turned on themselves in the one dimension (thus at least partially rolled up) without compression, or further compression, and will serve to compress or further compress those bodies in their thickness as they turn on themselves or roll up in that space. Effectively, a spinning action can be produced for the pad-like bodies operated upon in succession. It will be appreciated that an entrant pad-like foam body needs to enter the second means between spaced ones of the bounding rollers, and will first contact both of those two spaced bounding rollers, one by each of its main surfaces; but that, thereafter, only one of the main surfaces of each of successive pad-like foam bodies will be contacted by the others of the bounding rollers, and it is preferred that the bounding roller contacted by the other of those main surfaces be an idler capable of either direction or rotation. It is preferred that whatever is considered to be actual entry to the second means not only be of substantially the same spacing or width as entrant pad-like foam bodies, thus the same as (or maybe less than) whatever is considered to be actual exit from the first means, but that it be closely concatenated physically with exit from the first means, say with entry rollers of the second means following close on to preferred pre-compressing exit rollers of the first means (if not actually or effectively the same) . It is preferred that the third means comprises a pushing mechanism to engage one end of a compressed pad- like foam body while still in the second means, and effective to translate same, other end first, from the second means; then into a constraining guide that prevents any expansion (other than might actually be desired or provided for by design) of the compressed pad-like body, or controls any permitted then probably small) expansion thereof. Such a guide may be effectively part of the fourth means, say as a former for wrapping sheet fed in the same direction as translation of the compressed pad-like bodies. Such a wrapping sheet can be joined edge portion to edge portion in its direction of movement, and such joining may be done as or after the compressed pad-like bodies leave the guide. A suitable third means comprises a drive chain, belt or the like, conveniently of endless type, carrying upstanding pushers with ends to engage the compressed pad¬ like bodies and upstands that pass between two of the bounding rollers of the preferred second means and a space in or slot down the preferred guide. Use of continuous wrapping sheet enables virtually any desired spaces to be left between wrapped compressed pad-like articles to facilitate sealing the sheet to both sides of severance positions so that packed articles are sealed all round. The following exemplary description indicates how practical implementation can be achieved, when taken in conjunction with the accompanying diagrammatic drawings, in which:- Figure 1 is a general plan view of an installation embodying this invention; Figure 2 is a side elevational view of provisions for compression before wrapping; and Figure 3 is an end or sectional view of compression provisions. In the drawings, pad-like foam bodies are shown before compression at 10 as being generally flat and rectangular in plan with a length greater than their width and a much lesser thickness. Preferred compression ultimately results in articles of much smaller size or volume and a much different shape, specifically cylindrical as shown at IOC. Desired impregnants for those bodies can be of fluid type, often liquid, and may be applied at any convenient time and in any convenient manner, whether before presentation to the illustrated installation or afterwards, say before or after or during compression, but the volume of impregnant should ideally never exceed the holding capacity of the bodies IOC after compression (at least unless it is tolerable for excess to be expressed during compression) . Alternatively, suitable impregnants can be dry, say as powdrous inclusions, or as releasable ingredients of the foam material itself, in both cases normally subsequently "activated" for use by liquid, most often water. These indications are made wholly without limiting intent as anything that can be compressed from pad-like form to a lesser volume in the manner to be described is suitable for practising this invention. Changing the shape of the pad-like bodies 10 involves turning them on themselves thickness-upon-thickness, and, as shown, extends to spiral rolling up through at least one full turn (360-degrees) , preferably substantially more than one full turn, entirely feasibly (but not necessarily) more than two full turns. Such turning of the pad-like bodies on themselves, or rolling up, is shown accompanied by compression in a stage 20 that is referred to herein as a spinning station. H.owever, and highly advantageously but certainly not necessarily, that spinning station 20 is shown as achieving less than the full ultimate article compression, see reference 10B for a somewhat larger diametric dimension than applies for reference IOC. The spinning station 20, see particularly Figure 3, is shown comprising an interior space 21 within an assembly of rollers 22 that effectively bound and define the space 21. The interior space 21 is shown as nominally circular cylindrical by use of a dashed circle touching innermost overall radial points of the rollers 22, i.e. geometrically circumscribed by those rollers 22, and the outer side of the dashed circle will correspond to nominal diameter of the extent of compression represented by the reference 10B (ignoring any excursions outwardly between the bounding rollers due to resilience of the material of the pad-like bodies) . The bounding rollers 22 are shown with their axes spaced about a cylindrical locus 23, also shown dashed, with roller-to-roller spacings at 24 and 25 for entry of pad-like bodies 10 and passage of pusher upstands 42 (further described below) , respectively, and will be mounted in or on some suitable carrier or framework 26 (not shown in detail for clarity) . The bounding rollers 22 are further indicated as being of two different types, one (22A) for one direction of rotation only and the other (22B) able to rotate in either direction. All of the rollers 22A contribute to turning the pad-like bodies on themselves, or spirally rolling and compressing them, and can all be both driven and have surfaces that are knurled or otherwise rendered of a gripping nature for the engaged surface of the pad-like bodies 10 as they are formed and reduced substantially to match the interior space 21. It may not be necessary to drive all of the rollers 22A, nor for them all to be of surface gripping type, perhaps not even that roller 22A flanking . the pad-like body entry gap 24 (though that is presently seen as advantageous and thus preferred) . The roller 22B is conveniently an idler, further preferably with a non-gripping surface relative to the pad-like bodies, and will need to rotate in one direction opposite to the rollers 22A during entry of a pad-like body (assuming contact with the roller 22B as is preferred), then reverse its direction of rotation to be the same as the rollers 22A when a pad-like body is wholly within the space 21 and is being spun round prior to removal from the space 21 (as is further preferred) . Such spinning within the space 21 is effective in asserting the nominal boundary of the space 21 onto the pad-like body 10B, i.e. in minimising any tendency for that body 10B to expand outwardly between innermost points of the bounding rollers 21, whether generally or particularly at the gaps 24,25. Feeding of the pad-like bodies 10 to the spinning station 20 can be done in any convenient way, but preferably one using a conveyor capable of high speed operation, and a vibratory track provision 30 is seen as particularly suitable, as shown with holding and entry gates 31 and 32, respectively, both shown as of opposed reciprocable element type, see 31A,B and 32A,B and arrows for movement. In-feed to such a vibratory track can be of a conventional nature, say from a drum type provision (not shown) . Exit from the in-feed conveyor 30, or first stage of entry to the spinning station 20 is shown by way of spaced counter-rotating rollers 26A,B adjacent the rollers 22A,B, respectively. From Figure 3, it will be appreciated that the spacing 27 between the rollers 26A,B is less than the thickness of the pad-like bodies 10 so that some degree of precompression in the thickness (10T) of the pad-like bodies is envisaged between the rollers 26A,B, even a little more again between the rollers 22A,B flanking the gap 24 (see their lesser again spacing 24), and such provisio (s) assist succeeding operation of the spinning station 20. Removal of the formed and reduced pad-like bodies 10B is shown achieved by a pusher system 40 using a head 41 that is rotatable (see journal 43) on an upstand 42 that is movable through the gap 25 between spaced bounding rollers both referenced 22A. In fact, the pusher system 40 is shown with plural heads 41 on spaced upstands 42 extending from a suitable drive shown as chain, and preferably an endless chain 44 (though any suitable drive system could be used) . The pusher system 40 translates the pad-like bodies into a track or path with radial constraint to prevent unwanted or unacceptable expansion of the articles from the state achieved in the spinning station 20, and actually shown as further compressing the pad-like bodies 10B to the state referenced 10C, with the pushers 41,42 operative to traverse the radially constraining path or track too. A suitable such track or path can be defined by the interior of a tube 50 having a flared entry 51 and a lengthwise slot 52 for the pusher upstands 41. . Additional compression after the spinning station 20 can be advantageous in aiding attainment of more nearly uniform compression of the pad-like bodies in final articles, at least if there is any tendency for the turning or rolling and spinning to produce differential compression of thickness that is greater at the centre than at the exterior at the stage referenced 10B. The track or path represented specifically by the flared and slotted tube 50 can lead to, even constitute an entry part of, a wrapping station (not shown), say with wrapping sheet material passing in a U-fold over the tube 50 and with its sides joined together just beyond return provision of the pusher chain 44. A suitably strong wrapper material can be used to retain compression up to that referenced IOC for the pad-like bodies. Moreover, wrapping can be on a flow-line basis, and can extend to making seals between ends of the pad-like bodies as shown progressing in spaced relation, to afford completely sealed final articles.

Claims: CLAIMS 1. A method of forming and packaging pad-like articles of resilient compressible foam having one dimension (thickness) smaller than its other two dimensions, the method comprising the successive steps, for successive articles, of: (a) feeding the pad-like articles successively into an entry to a compression mechanism having an interior space nominally corresponding to exterior compressed form of the pads as desired for the articles and an entry to the interior space that is preferably not wider than the one dimension (thickness) of the pads prior to compression (b) turning each pad on itself in the interior space of the compression mechanism to compress it in the one dimension (thickness-upon-thickness) by movement of bounding surfaces of the interior space (c) pushing the compressed pads from the compression mechanism transversely to said movement of bounding surfaces of the interior space (d) forming a package as a said article by applying a containing wrapping about the rolled up pads outside the compression mechanism. 2. Method according to claim 1, wherein the articles are effectively spun in the interior space of the compression mechanism at completion of their turning on themselves in the one dimension so as to be at least partially rolled up as translated therefrom. 3. Method according to claim 2, wherein the articles as at least partially rolled up are translated into a guide about which continuous wrapping sheet is fed and formed to enclose the rolled up articles. 4. Method according to claim 3, wherein the wrapping material is sealed to itself both lengthwise of the rolled-up articles and between them. 5. Apparatus for forming and packaging articles of resilient compressible foam, comprising first means for feeding pad-like foam bodies each having one dimension (thickness) less than its other two dimensions with a leading edge in said one dimension; second means for accepting said pad-like foam bodies by their leading edges first into an interior space within which said pad-like foam bodies are turned on themselves in the one dimension for at least partial rolling up (thickness-upon-thickness) , by movement of one or more parts bounding that interior space; third means for translating such rolled-up bodies from the second means transversely of movement of the bounding part or parts; and fourth means for accepting such rolled-up bodies from the second means and applying a constraining wrapping thereabout. 6. Apparatus according to claim 5, wherein the first means serves both to feed the pad-like foam bodies and begin compression of them, and has an exit of lesser spacing than the thickness of the pad-like bodies. 7. Apparatus according to claim 6, wherein the first means comprises rollers at said lesser spacing. 8. Apparatus according to claim 7, wherein the rollers include a pair of driven rollers opposite another driven roller. 9. Apparatus according to claim 8, wherein the pair of rollers is disposed above the other roller. 10. Apparatus according to any one of claims 7 to 9, wherein some or all such rollers is or are of surface- gripping type relative to the pad-like foam bodies. 11. Apparatus according to any one of claims 5 to 10, wherein the second means presents a cylindrical locus for axes of rollers constituting its moving parts and bounding its said interior space within which compression takes place. 12. Apparatus according to claim 11, wherein at least some of those bounding rollers are driven. 13. Apparatus according to claim 12, wherein the rollers serve to turn the pad-like bodies on themselves in compressing them in the one dimension in the interior space with a spinning action for the pad-like bodies operated upon in succession in that interior space. 14. Apparatus according to claim 11, 12 or 13, wherein two of the bounding rollers are spaced to form an entry for the pad-like bodies into the interior space and make first contact each with a different one of main surfaces of the pad-like bodies. 15. Apparatus according to claim 14, wherein others of the bounding rollers contact only one of the main surfaces of each of successive pad-like foam bodies, and the " π one of the two bounding rollers spaced to form an entry and contacting the other of those main surfaces is an idler capable of either direction of rotation. 16. Apparatus according to any one of claims 5 to 15, wherein entry or said entry to the second means is not less than exit from the first means and is closely concatenated physically therewith. 17. Apparatus according to claim 16 with claims 6 and 13, wherein entry rollers of the second means follow close on to pre-compressing exit rollers of the first means. 18. Apparatus according to any one of claims 5 to 17, wherein the third means comprises a pushing mechanism to engage one end of a compressed pad-like foam body while still in the second means, and operative to translate the compressed pad-like body other end first from the second means. 19. Apparatus according to claim 18, further comprising a constraining guide that prevents undesired expansion of the compressed pad-like body pushed out of the second means. 20. Apparatus according to claim 19, wherein the guide forms part of the fourth means as a former for wrapping sheet fed in the same direction as translation of the compressed pad-like bodies to be joined edge portion to edge portion in its direction of movement as or after the compressed pad-like bodies leave the guide. 21. Apparatus according to claim 12, wherein the third means includes an endless flexible drive member carrying upstanding pushers with ends to engage the compressed pad-like bodies and upstands that pass between two of the bounding rollers.

Inventors: JEFFREY PETER, TOFT JOHN FRANCIS, JEFFREY, PETER, TOFT, JOHN, FRANCIS
Applicants: JEFFREY PETER, NUCLEUS ENTERPRISE LTD, TOFT JOHN FRANCIS, JEFFREY, PETER, NUCLEUS ENTERPRISE LIMITED, TOFT, JOHN, FRANCIS
Application year: 1994
Main classification: B65B63
IPC codes: B65B63